GT500 plug reading? Bad o2 sensor?

My 14 GT500 has a slight hesitation/misfire. Pulled the plugs today and found Bank 2 to be completely fouled. Bank 1 looks great. Does this look like the o2 sensor is stuck lean on bank 2? Also did a log on my SCT and Bank 2 was pegged lean and did not move, while bank 1 fluctuated around normal.

Jumping in full tilt, regardless of CEL's I'd first check for any obvious exhaust leak between the exhaust manifold up to the O2 sensor on bank two. Exhaust leaks small or large will effect the O2 sensor reading which will give a false lean indication when in fact the A/F Ratio in the combustion chamber is fine otherwise. This causes the PCM to add pulsewidth to the injectors introducing more fuel into the cylinder. If the O2 sensor has failed and is putting out little to no voltage, again the PCM thinks the sensor is seeing a lean condition and increases fuel (pulsewidth on the FI) when in fact the ratio was fine to begin with.

The rear O2 sensor should detect a failure or clog in the Cat IF IT HAS NOT BEEN TURNED OFF IN A TUNE. Visual inspection of the Cat would indicate a possible clog, as bank 2 which is on the driver's side would show signs of extreme heat up near the entry of the cat. Plus chances are you would feel warmer than usual temps near your foot when driving. While there is the H-pipe in the system it may also still be possible to feel heavier exhaust flow on the passenger side rear than the drivers side rear...maybe. The eyeball inspection of the cat and the hotter floor board temps on the driver's side would be the better tell tails.

There are no codes present. No cats on the car. VMP tune, long tube headers, off road x pipe, o2 extensions and other bolt ons are the mods. No leaks are present either. Rear o2s are switched off. It is definitely dumping fuel on that side. I'll check the o2 extensions and sensor tonight.

There are no codes present. No cats on the car. VMP tune, long tube headers, off road x pipe, o2 extensions and other bolt ons are the mods. No leaks are present either. Rear o2s are switched off. It is definitely dumping fuel on that side. I'll check the o2 extensions and sensor tonight.

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Swap O2's if you see no indications of burned or broken wiring on bank 2 harness. Obviously we are hoping that the symptom moves to bank 1. Then you know its the O2 sensor.

It's a factory wideband, correct? It's pegged for sure and overfueling the whole bank. Why it's pegged is the question. Sensor or extension?

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Yes it is the factory wideband o2. I just realized it was the first time I'd driven the car in the rain since I put the headers on, next start up is when this happened. I wonder if the extensions are more sensitive to water than the factory plug ins? Not feeling so great today so will have to work on it tomorrow.

Looks like the o2 sensor itself is the culprit. First, I removed the extension and plugged it in directly, still same issue. Swapped it over to Bank 1 and the readings moved along with it. I completely forgot to order one the other day, so hopefully I can get one locally tomorrow. I will be doing a clutch swap this weekend so that will be a good time to go through and stretch out the harness so I can make sure the wires are comfortable and not being stretched too far.

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Looks like the o2 sensor itself is the culprit. First, I removed the extension and plugged it in directly, still same issue. Swapped it over to Bank 1 and the readings moved along with it. I completely forgot to order one the other day, so hopefully I can get one locally tomorrow. I will be doing a clutch swap this weekend so that will be a good time to go through and stretch out the harness so I can make sure the wires are comfortable and not being stretched too far.

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Figured that was the culprit. Good trouble shooting.

Mark those harnesses well. Getting them crossed is a common OH-OH when doing a clutch swap. Label properly once...plug in properly once.